System for removing impurities from steam boilers



July 27,1926.

C. T. MCGILL SYSTEM FOR REMOVI'NG IMPURITES FROM STEAM B0 ILERS Enea ,1p1-11 18, 1925 NNQ ,NML

l V attoznmp Patented July l227, 1926.

UNITED STATES y N y .1,593,700 PATENT OFFICE.

CHESTER THOMAS MCGILL, OF ELGIN, ILLINOIS. ASSIGNOR T0 REITER C0., 0F '.ELGFIN. Y ILLINOIS, A CORPORATION OF ILLINOIS..

SYSTEM FOR REMOVING IMPURITIES FROM STEAlVI ,BOLERS Application led April 18, 1925. Serial No. 24,233.

This invention has for its prime object the removal of impurities from a horizontal return tubular type of steam boiler while in operation, or any other type of boiler,l

without the use of pumps or other special machinery. .y 'It is a practice to test and treat boiler feed water while the boiler is4 in operation by .means of some system of softening land purifying boiler water, whereby the Various impurities are placed in suspended form so that they can be more easily removed, preferably in the manner described and claimed in this application.

An object of this invention is to removel with the water romthe boiler and depositV it in the precipitator where it may be blown out into the sewer or otherwise disposed of.

Another object of this -invention is to provide a method and apparatus whereby t-he boiler may be kept clean during operation of the plant, by removing the impurities from the boiler water while 'the boiler is unordinaryl boiler.`

Fig. 2 is an elevation View of the lower section ofthe precipitator tank, showing the arrangement. of valves and pipes attached thereto.

The numerals 1 and 2 designate the surface and bottom water supplies within an ordinary boiler of a suitable type, while the numeral 3 represents a precipitator tank, located at a convenient point with respect to the boiler. The numeral 4 designates the return pipe line as a whole leading from the precipitator tank to the boiler, while 1s the main blow 0E valve from the pre'cipltas tor. 6 designates the blow of;` valve in the pipe leading :from the surface or top of precipitator 3, the numeral 7 represents the inal blow oi valve controlling the discharge to the sewer or otherwise.

A valve 9 is locatedbetween :the return line portions 33 and. 26 from the precipitator 3. Numeral 10 designates the automatic air trap, while 11 and 12 are pipe connections, and 13 and 14.- designate supply line iittings.

The numeral 1,5 represents the pipe connections to the air trap 10, and 16 the air cushion pipe and c`ap,`while 17 refers to the air trap valve, 18 and 19 are pipe nipples, and 20 is an eiitra heavy connection to the precipitator tank. The numeral 21`designates a special T fitting with a blind end, vwhile 22 represents the nipple stand, and 23 the floor plate for the tank. Thesurface blow down line from-the precipitator is represented by the numeral 24, and 25 is a cross connection therefrom, while 26 is lowermost portion of the returnconnection to the boiler. The supply line 27 to the system has a special pipe fitting 28 inside the'boiler to accommodate the surface supply and bottom supply pipes, 1 and 2. z The numeral l29"designates a sleeve for covering .the return portion of the pipe line 4, while 30 is a vent pipe from air trap 10, and 31 is a water sample valve. The valve in the pipe leading from the air trap 10 is represented by numeral 32, while 33 designates the upper portion of the return pipe line froml the precipitator 3 to the boiler. In operation the water is supplied to the boiler in the usual manner from the source of supply. During the process -of feeding land heating, the water is tested and treated,

thereby placing the' impurities in a suspended foi-1n so that they may be readily handled by this invention. The procedure is carried ont in general by first noting that valves 17, 6, 31 and 32 are opened, then opening valve 9 until the precipitating tank fills with boiler water. The air contained in the precipitator 3 is dislodged through the pipes controlled by valves 6, 17, 32, and 31, also pipe 30. When the air is all out close valves 6, 31 and 32. Valve 8 may then be opened and the Asystem is in operation. Valves 8 and 9 are wide open during the operation of the system.

The system is supplied with waterthrough pipes 1 and 2 inside of theboiler. f

The water returns from `the preeipitator 3 back to the boiler through the line controlled by valve 9. The arrows indicate circulation. The light lilocculent matter is `drawn oi through the line controlled by valves 6 and- 7 t0 the :Sewer or through the line controlled by valves 6 and 31 to a pail or other receptacle. The heavy sediment, soft lime' or other residue may be drawn out from the precipitator 3 through the line controlled by valves 5 and 31 into a pail or other receptacle, or may be blown into the sewer through the line controlled by valve 7.

This invention particularly' provides a means consisting of a combination with a boiler structure of a system for removing impurities from the water thereof, said system comprising a precipitator, a pipe extending from the boiler to the precipitator and having one end arranged below the normal water level in the boiler and its second end disposed in the precipitator and a return line arranged to convey purified water from the precipitator to the boiler and including a portion inclined upwardly, through the combustion chamber toward the boiler shell and a shield surrounding the upwardly inclined portion and spaced therefrom and communicating with the interior of the combustion chamber. y

It is apparent from the above description, that by taking samples from the top of the precipitator, the bottom of the precipitator and from the air trap line, an indication may be obtained as to how well the precipitator has removedI certain solids and in what proportions it has reduced the concentration of suspended, as Well as soluble matter. Also, bytaking the 'samples from the bottom of the preciptator, an indication is obtainedas to how well the precipitator has functioned and, of course, these samples have considerable to do with what the next step of the operator would be in properly conditioning the water in the boiler. Obviously, the sample taken from the air trap `line is the same as the water in the boiler and indicates the condition of the boiler water and the kind of sediment to be removed in the precipitator.

In this connection, it may be further stated thatthe Water which is ordinarily supplied direct to the boiler, would carry so many grains of hardness per gallon that a portion of the scale forming solids would be neutralized and precipitated by the heat,

the remaining solids being neutralized by chemical treatment.

Knowing the amount of evaporation in a boiler and the hardness contained in the Water and the amoimt of treatment required for each one thousand gallons of water, it 1s known definitely. how much sediment and solids are to be removed by the system according to this invention. In other words, it is known within a very close approximation the number of pounds of solids the system will remove hourly from the boiler.

These solids are usually blown to-the sewer without any measuring of the solids; however, they can be drawn ot in a pail o r barrel and it can be determined quite accurately whether all the solids are being removed.

By taking a sample of water from the air trap line through valves 32 and 31. it en- 'alile's the operator to tell definitely the condition of the water as it travels from the boiler to the precipitator; By testing this water, it indicates whether the water is soft, the amount and kind of treatment in excess, and whether the water is carrying a sufcient amount ofsediment to keep the boiler clean. In every water there is light tlocculent matter which has a lighter specific gravity than the water itself. These solids are accumulated at the top of the precipitator out of the regular current or travel ofV the water and by drawing water'oft through line 24 and valves 6 and 31 for test purposes', indicate whether lthis end of the precipitator is getting as much of these light flocculent solids as it should get hourly.

Then taking samples from the bottom of theprecipitator through line 20 and valves 5 and 31 indicates whether the bottom portion of the precipitator is functioning etliciently and removing all of the sediment that have a heavier specific gravity than the water.

The operator soon gets to the point where. as soon as he draws a sample from any of these three places, he knows fairly well what results are being obtained at the other two points. For illustration :--a sample of water taken from the air trap through the line controlled by valves 32 and 31, would indicate the amount of sediment being carried in circulation to the precipitator and would indicate whether this sediment settled out readily at the bottom or accumulated at the top of the sample. In this way, without making any further tests, be can be guided in just what to do to further condition the water in the boiler. In doubtful cases, the samples from the top of the precipitator and the bottom of precipitator will indicate the proper procedure to take.

What I claim is 1. The combination with a boiler structure, of a syst-em for removing impurities from the water thereof, said system comprising a precipitator, a pipe extendingI from the boiler to said precipitator and having one end arranged below the normal water level in the boiler and its other end disposed in the precipitator, a return line arranged to convey puried water from said precipitator to the boiler and including a portion inclinednpwardlv tlrough the combustion chamber toward the boiler shell and a shield surrounding Jhe upwardly inclined portion and spaced therefrom and communicating with the exterior of the boiler wall and the interior of the combustion chamber.

2. The combination with a boiler structure of @System for removing vimpurities from the water thereof, lsaid system including a precipitator, a discharge line projecting upwardly from a point below the normal Water level of the boiler, a Ipipe extending upwardly from said precipitator, a pipe inclined upwardly from the discharge line to the first mentioned pipe, a return line ar` rangedto convey purified water vfrom the precipitator to the boiler and' including a portion inclined upwardly through the combustion chamber toward the boiler, and a shield surrounding the inclined portion andA bbetween said precipitator Iand trap, a blow olf line leading from said precipitator, said trap includingsedimentation chamber, and avalved pipe connecting said air trap 'sedimentation chamber with the blow-off line from said precipitator.

' 4. In a boiler water purifying system, the combination of a precipitator, a pipe extending upwardly therefrom, an air trap.

communicating with the upper portion of said pipe, aconduit connected to said ipe between said'i precipitator and trap, a b owoff line leading from said precipitator, said trap including sedimentation chamber, and a valved pipe connecting said air trap sedimentation chamber with theeblow-o line from said precipitator, and means communicating with the valved pipe for removing samples therethrough from the chamber.

5. In a boiler purifying system, the combination of a precip1tator,.a pipe extending.

upwardly therefrom, an a1r trap communicating with the upper portion of said pipe, a supply line leading from the boiler to the topof the precipitator, a return line from the precipitator to the boiler and means for removing samples of water from the top of the precipitator, the bottom of the precipitator and from the air trap, thereby making it possible to note the eiciency of the precipitator, and in what proportions it has reduced the concentration of suspended, as

well as soluble matter, the means for remov- -ing samples from the top,and bottom of the precipitator being adapted to draw ofl the impurities which accumulate.

In testimony whereof I aiiix 'my signature.

CHESTER lTHOMAS MGGrILL. l 

